The present invention relates to improved biocide compositions based on calcium fluoride which are suitable for a broad range of applications including the provision of antimicrobial activity on living tissue/skin, such as medical antiseptics, the provision of antimicrobial activity on other surfaces, such as general disinfectants in medical and nonmedical fields, and/or the provision of antimicrobial activity or prevention of microbial activity, in particular fungal activity, in non-living objects, such as additives to construction materials and paints.
Generally, it is desired to have fast acting and persistent antiseptics and disinfectants.
Antiseptics or disinfectants are usually considered as “fast acting” if they achieve a significant reduction of the number of target microorganisms in a time period of less than minutes following application of the antiseptic.
The term “persistence” relates to the ability of the antiseptic to maintain its antimicrobial activity once it is applied and is connected with the retention of or binding of the agent on the respective surface, e.g. the stratum corneum of the skin, after partial evaporation and after rinsing. The persistence can be measured by the time required for the microflora to be restored to the baseline before the application.
Currently, there are several very fast acting antiseptics, effective within 20 seconds against pathogenic microorganisms, commercially available. Most of these antiseptics are based on alcohols, iodine solutions or chlorides. However, all the conventional fast acting antiseptics cannot prevent fast repopulation of the treated surface, such as skin. In particular in the latter case this effect is at last partially due to the fact that the natural body protection (fatty acids, presence of balanced salts, regulated pH etc.) against microbial invasions has also been destroyed.
U.S. Pat. No. 8,445,030 B2 discloses antiseptic or disinfectant compositions based on calcium fluoride which are both persistent and fast acting. In these compositions, the mineral calcium fluoride acts as the persistent component which sticks to the skin or surface for long periods and releases its antimicrobial acting fluorine ions only on “demand”, such as in a warm and moist environment. This reference further discloses that highly toxic antiseptic compounds, such as hypochlorite or hydrogen peroxide, are added in a very low percentage in order to initiate and amplify fast antiseptic action on microorganisms.
It is also disclosed that other antimicrobial agents such as ethanol, salicylic acid esters, cinnamic acid, quinic acid, citric acid may be added to improve the antimicrobial efficacy of the claimed compositions.
However, in view of the typical presence of aggressive and toxic components such as hypochlorite or hydrogen peroxide, albeit in low concentrations, in said antiseptics, there is still a demand for further improved compositions which do not require the presence of hypochlorite or hydrogen peroxide and show the same or even better performance as that exhibited by the compositions of U.S. Pat. No. 8,445,030 B2.
In this respect, WO 2012/104718 A2 discloses that the presence of long-chain polymers (MW typically 40.000 or more) which provide a porous sponge-like structure, protecting the underlying and securing the reservoir against mechanical abrasion and wash-off, in a calcium fluoride based composition results in an effective water-based antiseptic spray. However, this document provides only a rather general teaching and does not disclose specific polymers and specific compositions for different applications comprising the same.
In view of this prior art, the object underlying the present invention is to provide further improved and optimized specific biocide compositions based on calcium fluoride which are essentially non-toxic, show an excellent antimicrobial performance, long-term stability, and are advantageously applicable for a broad range of medical and nonmedical applications.
This object is achieved by the composition of the invention.